St. Nicholas Church, located in Krakow (Cracow), Poland, is one of the oldest monuments in Cracow. The oldest mention of the church dates back to 1229. It was designated as a parish church in 1327. After much redesign and rebuilding over the centuries, the church is currently classified as a baroque and neo-baroque three-nave, three-bay basilica.

The current construction was built on an already-existing foundation from the structure destroyed in the past. The stones used for the foundation and the limestone rock on which the church is located were subjected to washout and karst phenomenon over the centuries, leaving severe degradation. Acid water washout, as well as vibrations caused by increasing traffic—especially on the train track located just behind the church—were other causes of the severe deterioration of the foundation. This all led to the front wall deviating from vertical and falling away from the structural walls.

Cracking was seen in the chancel vaults, main nave, and the aisles, which resulted from a lack of rigid support, receiving the strutting forces through the walls. The original timber framing was not enough to stabilize the structure, so steel framing and braces were installed throughout the attic of the church, hidden to normal visitors. This new reinforcement allowed even transfer of the strutting forces through the walls, and movement of the church was decreased significantly.

After the repairs were completed, the building was reopened to the public in 2012. As required by the Cracow Monument Preservation Office, a yearly inspection is made on the entire structure to check for durability of the repair and, if any issues do arise, they can be addressed as quickly as possible.